Cargando…

Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study

l-theanine (γ-glutamylethylamide), an amino acid in green tea, has been shown to affect brain functions by relieving stress disorders, improving mood, and maintaining normal sleep. However, the cognitive functions for which theanine is effective are unclear. This study aimed to clarify which cogniti...

Descripción completa

Detalles Bibliográficos
Autores principales: Baba, Yoshitake, Inagaki, Shun, Nakagawa, Sae, Kaneko, Toshiyuki, Kobayashi, Makoto, Takihara, Takanobu
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Mary Ann Liebert, Inc., publishers 2021
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8080935/
https://www.ncbi.nlm.nih.gov/pubmed/33751906
http://dx.doi.org/10.1089/jmf.2020.4803
_version_ 1783685538994192384
author Baba, Yoshitake
Inagaki, Shun
Nakagawa, Sae
Kaneko, Toshiyuki
Kobayashi, Makoto
Takihara, Takanobu
author_facet Baba, Yoshitake
Inagaki, Shun
Nakagawa, Sae
Kaneko, Toshiyuki
Kobayashi, Makoto
Takihara, Takanobu
author_sort Baba, Yoshitake
collection PubMed
description l-theanine (γ-glutamylethylamide), an amino acid in green tea, has been shown to affect brain functions by relieving stress disorders, improving mood, and maintaining normal sleep. However, the cognitive functions for which theanine is effective are unclear. This study aimed to clarify which cognitive functions are positively affected by intake of l-theanine. A double-blind, randomized, placebo-controlled study was conducted. The subjects were Japanese men and women aged 50–69 years. Mini Mental State Examination-Japanese version score was 24 or higher. Cognitrax was used as a test battery for cognitive function. Evaluations were performed before the intervention, after a single dose of l-theanine, and after 12 weeks of regular intake. The single dose of l-theanine reduced the reaction time to attention tasks (Stroop test, Part 1), and it increased the number of correct answers and decreased the number of omission errors in working memory tasks (4-Part continuous performance test, Part 4). In conclusion, our study indicated that l-theanine may contribute to improving attention, thus enhancing working memory and executive functions. Clinical Trial No.: UMIN000033812.
format Online
Article
Text
id pubmed-8080935
institution National Center for Biotechnology Information
language English
publishDate 2021
publisher Mary Ann Liebert, Inc., publishers
record_format MEDLINE/PubMed
spelling pubmed-80809352021-04-29 Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study Baba, Yoshitake Inagaki, Shun Nakagawa, Sae Kaneko, Toshiyuki Kobayashi, Makoto Takihara, Takanobu J Med Food Full Communications l-theanine (γ-glutamylethylamide), an amino acid in green tea, has been shown to affect brain functions by relieving stress disorders, improving mood, and maintaining normal sleep. However, the cognitive functions for which theanine is effective are unclear. This study aimed to clarify which cognitive functions are positively affected by intake of l-theanine. A double-blind, randomized, placebo-controlled study was conducted. The subjects were Japanese men and women aged 50–69 years. Mini Mental State Examination-Japanese version score was 24 or higher. Cognitrax was used as a test battery for cognitive function. Evaluations were performed before the intervention, after a single dose of l-theanine, and after 12 weeks of regular intake. The single dose of l-theanine reduced the reaction time to attention tasks (Stroop test, Part 1), and it increased the number of correct answers and decreased the number of omission errors in working memory tasks (4-Part continuous performance test, Part 4). In conclusion, our study indicated that l-theanine may contribute to improving attention, thus enhancing working memory and executive functions. Clinical Trial No.: UMIN000033812. Mary Ann Liebert, Inc., publishers 2021-04-01 2021-04-16 /pmc/articles/PMC8080935/ /pubmed/33751906 http://dx.doi.org/10.1089/jmf.2020.4803 Text en © Yoshitake Baba, et al., 2021; Published by Mary Ann Liebert, Inc. https://creativecommons.org/licenses/by-nc/4.0/This Open Access article is distributed under the terms of the Creative Commons Attribution Noncommercial License [CC-BY-NC] (http://creativecommons.org/licenses/by-nc/4.0/ (https://creativecommons.org/licenses/by-nc/4.0/) ) which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and the source are cited.
spellingShingle Full Communications
Baba, Yoshitake
Inagaki, Shun
Nakagawa, Sae
Kaneko, Toshiyuki
Kobayashi, Makoto
Takihara, Takanobu
Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study
title Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study
title_full Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study
title_fullStr Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study
title_full_unstemmed Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study
title_short Effects of l-Theanine on Cognitive Function in Middle-Aged and Older Subjects: A Randomized Placebo-Controlled Study
title_sort effects of l-theanine on cognitive function in middle-aged and older subjects: a randomized placebo-controlled study
topic Full Communications
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8080935/
https://www.ncbi.nlm.nih.gov/pubmed/33751906
http://dx.doi.org/10.1089/jmf.2020.4803
work_keys_str_mv AT babayoshitake effectsofltheanineoncognitivefunctioninmiddleagedandoldersubjectsarandomizedplacebocontrolledstudy
AT inagakishun effectsofltheanineoncognitivefunctioninmiddleagedandoldersubjectsarandomizedplacebocontrolledstudy
AT nakagawasae effectsofltheanineoncognitivefunctioninmiddleagedandoldersubjectsarandomizedplacebocontrolledstudy
AT kanekotoshiyuki effectsofltheanineoncognitivefunctioninmiddleagedandoldersubjectsarandomizedplacebocontrolledstudy
AT kobayashimakoto effectsofltheanineoncognitivefunctioninmiddleagedandoldersubjectsarandomizedplacebocontrolledstudy
AT takiharatakanobu effectsofltheanineoncognitivefunctioninmiddleagedandoldersubjectsarandomizedplacebocontrolledstudy